Hi,

Le vendredi 21 janvier 2011 17:55:50, vous avez écrit :
> I am finding that amcheckdump (3.2.0) gets sporadic failures with messages
> like
> 
> Reading volume AMB009L4 file 9
> Validation errors:
> Error writing to fd 9: Broken pipe
> /bin/gzip exited with status 1

maybe you should check the logs to have the gzip error message ?

> 
> A similar problem was reported in
> http://www.mail-archive.com/[email protected]/msg44288.html
> but I'm not sure whether it is meant to be fixed in 3.2.0.
> 
> In my configuration tar is not involved, the backup files are in
> compressed dump format. So amcheckdump creates a pipe containing gzip and
> restore; presumably gzip terminates when it gets to the end of the real
> data and does not bother reading the zero padding at the end of the last
> block. Unlike with tar I don't know any way of forcing gzip to
> read till the bitter end.
> 
> My blocks are 512kB and they are read over a slowish iscsi connection so
> that possibly gives gzip plenty of time to process its data while the
> rest of the block is still being read.
> 
> I can live with the problem, but it is a bit irritating so any comments
> welcome.
> 
> Bob

not sure it is related but I had some similar problem when trying to write my 
own verification script. I did something like that :

amfetchdump -p -h ... > FETCH_PIPE &
( dd bs=32k of=HEADER_PIPE count=1; dd bs=32k of=DUMP_PIPE; ) <FETCH_PIPE &
cat HEADER_PIPE # parse header to know which tools we need to unpack...
gzip -d <DUMP_PIPE | tar -xf- &
wait

it was 'almost' working with some random failures which looked like yours 
(gzip failed because datas are 'not in gzip format' causing amfetchdump to die 
with a broken pipe). The strange thing is that a given dump will sometimes 
work and sometimes not. I finally discovered that when it fails the header I 
get has a wrong size (<32k) so I added 'iflag=fullblock' to the first dd call 
and it seems to have solved the problem. Looks like you're not using 
amfetchdump yourself but maybe amcheckdump does the same mistake behind your 
back ? 

Hoping it may help someone...

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